Ok, to access the bios you usually repeatedly hit the DEL button as soon as it makes the first beep as you start or restart your pc.
Some pcs use F1 or F2 instead but it should say on the screen as its starting up which key you need to press to select Setup.
This will open the bios setup, be careful what you alter, if anything, as it can mess your pc up. If you do alter anything write down what it was and what you changed it to so that you can change it back if necessary.
At the top of the screen it should say which bios it is, usually Ami, Award or Phoenix.
The part that I want you to check and possibly change is on the first screen or if that screen has a menu, as is common on AMI bios, then select the CMOS setup one, usually the first option on the top of the left column.
Near the botom of that page it should have a section that says Halt On and then a box where you can select the various options, usually done by using the page up or page down keys, it should say at the bottom of the screen which keys do what.
It usually defaults to Halt On All Errors. Most people have it set to Halt On All But Keyboard Errors but for now I would like you to change it to show Halt On No Errors.
Once you have changed it usually you hit F10 on the keyboard to save changes and exit the bios, it wil ask if you want to save changes, type Y (for YES) and press the enter key and it will close down and restart the pc as normal.
Hopeully that should bypass whatever the keyboard error is thats stopping it loading fully although you may find that the keyboard doesnt work once you get the desktop up.
At least that way we can find out whether it actually is a keyboard related problem or something else that we need to look into